It was but 55 years ago that American Jewish leader Jacob Blaustein imposed on David Ben-Gurion a written agreement in which the latter acknowledged American Jewry's exclusive commitment to the US, respected "the integrity of Jewish life in the democratic countries," and conceded that "the Jews in the US do not live 'in exile.'"

Evidently, things have changed since American Jewry was more than five times as large as Israeli Jewry, and US Jewish leaders could speak with nearly patronizing confidence to the elected head of the Jewish state. According to data presented this week by the Jewish People Policy Planning Institute, based on studies by the demographer Sergio DellaPergola, America's 5.28 million-strong Jewish community is but 45,000 people larger than Israel's.

Not only does this mean that we are, at most, only a few years away from Israel's emergence as home to the world's largest Jewish community, it also reflects the disturbing phenomenon of a shrinking Diaspora.

On the face of it, Israel's emerging demographic status within the Jewish world is a happy development. Who would have dreamt - not only back when the Zionist movement was conceived, but even after Israel's establishment - that the Zionist enterprise would be so successful that for the first time since antiquity the Promised Land would host the world's largest Jewish community and seem well on its way to hosting more than half of the entire Jewish people?

Yet that is precisely where things are headed, considering that Israeli Jewry is growing rapidly while the Diaspora's current population of 7.75 million Jews is already a drastic 2.25 million people smaller than a mere 35 years ago, according to DellaPergola's studies.

This is anything but a welcome trend. Like Blaustein in his time, we reject Ben-Gurion's dogmatic view that all Jews should live in their ancestral land. The way we see it, the demographic and spiritual survival of the Diaspora is vital for the future of the Jewish nation in general, and the Jewish state in particular.

It follows that Israel cannot remain indifferent as the Diaspora shrinks. We, as the Jewish state, must get down to the business of nourishing the Diaspora. This effort should not be focused on the restoration of Jewish life in countries like Germany, Russia, Ukraine and Poland that have been the historic hotbeds and stages of catastrophic anti-Semitism. Rather, it should concentrate on assisting Jewish communities across the Western world - where they are most numerous and welcomed, and are threatened by assimilation because of that very success and acceptance.

The next government should formally define the revitalization of the Diaspora as a strategic aim. Such a resolution would entail a drastic re-thinking of the relations between Jerusalem and Babylon, which remain governed by an unwritten and anachronistic distribution of responsibilities whereby the Israelis sacrifice blood and their brethren money.

Israel has matured economically, and the share of foreign aid and donations in its GDP is hardly 2.5 percent and on the decrease. Our income per capita is on a par with the major economies of Europe, even if our level of defense spending necessarily remains much higher than in other Western nations.

Accordingly, Israel should be working with the Diaspora on programs to bolster Jewish education and identity. The panoply of efforts that are known to work, including Jewish day schools, Jewish camping, and educational programs in Israel - such as the birthright and Masa programs - should be fully funded as a joint project of Diaspora philanthropy and the Israeli government.

The Diaspora played a pivotal role in Israel's founding, for which every Israeli should be eternally grateful. The Diaspora, moreover, has much to offer Israel at this moment, particularly in the realms of Jewish pluralism and the integration of Judaism with modern life. Now it is time for us to return the favor, and give back as much as we have received. For this, the Jewish state was founded and therein lies its - and the Jewish people's - future.